I also have one. There is no heater option in the app, at least not on the IOS version.
I did some testing with mine (SP04S03A Partno 16240017), with the heater terminal connected (screw connector), just as the picture from
@RV Truck Camper
I have set the charge under temp to 3, release at 5.
For testing, I've connected a 12V 50W H7 halogen bulb between H and battery positive.
With no charge, nothing happens, also not when you reach the set threshold for the low temp disconnect.
When you apply charge, things are differently. With the temp above set under temp, it just charges, nothing special.
If the temperature of ANY of the sensors is below the set temp:
- Charging stops due to low temp
- H connector is switched ON, 12V between H and battery + (thus enabling heater), as long as the 'charge under temp' is not released
- When the temp rises above the set release value (and release delay is expired), heating is disabled and charging restarts. (Charge under temp is released)
Exactly the behaviour you want, there is no need to have the heating running without charge.
Thus: Conditions to enable the heater
- Temp of any of the sensors has to be below set temp (causing a low temp charge disconnect)
- Charge voltage must be applied (otherwise the low temp charge disconnect isn't triggered)
- Charging starts once the release threshold temp is reached, (+ delay value expires) , heater is disconnected
As for the temperature sensors: Mine had 2, and they don't have all to be in low temp: A single sensor detecting too low will work.
Note: I did load the previous settings from my 120A BMS. That one had less temperature sensors, so I had to enable NTC 1/2/3 for the 200A BMS to see all sensors (1 = PCB sensor, 2 and 3 are the external ones)